LONDON—Here’s a new warning from health experts:Sitting is deadly.
Scientists are increasingly warning that sitting for long periods—even if you also exercise regularly—could be bad for your health.And it doesn’t matter where the sitting takes place—at the office,at school,in the car or before a computer or TV—just the overall number of hours it occurs.Several studies suggest people who spend most of their days sitting are more likely to be fat,have a heart attack or even die.
In an editorial published this week in the British Journal of Sports Medicine,Elin EkblomBak of the Swedish School of Sport and Health Sciences suggested that authorities rethink how they define physical activity to highlight the dangers of sitting.
While health officials have issued guidelines recommending minimum amounts of physical activity,they haven’t suggested people try to limit how much time they spend in a seated position.
“After four hours of sitting,the body starts to send harmful signals,”said EkblomBak.She explained that genes regulating(调节) the amount of glucose(葡萄糖) and fat in the body start to shut down.
Even for people who exercise,spending long periods of time sitting at a desk is still harmful.Tim Armstrong,a physical activity expert at the World Health Organization,said people who exercise every day—but still spend a lot of time sitting—might get more benefit if that exercise was spread across the day,rather than in a single bout(一回).
Still,in a study published in 2009 that tracked more than 17,000 Canadians for about a dozen years,researchers found people who sat more had a higher death risk,whether or not they exercised.
“We don’t have enough evidence yet to say how much sitting is bad,” said Peter Katzmarzyk of the Pennington Biomedical Research Center in Baton Rouge,who led the Canadian study.“But it seems the more you can get up and interrupt this sedentary behavior,the better.”
Figures from a U.S. survey in 20032004 found Americans spend more than half their time sitting,from working at their desks to sitting in cars.
Experts said more research is needed to figure out just how much sitting is dangerous,and what might be possible to offset those effects.
“People should keep exercising because that has a lot of benefits,” EkblomBak said.“But when they’re in the office,they should try to interrupt sitting as often as possible,” she said.
【小题1】What is the best title for the text?
A.Not Sitting Too Much While Working |
B.How to Avoid Sitting Too Much |
C.Sitting Too Much Could Be Deadly |
D.More and More People Sit Too Much |
A.the more time you spend in exercising in a single bout(一回),the healthier you will be |
B.those who often sit too much are sure to grow fat or suffer from a heart attack |
C.regular exercise is effective to get rid of the side effects of sitting too much |
D.you had better not sit for more than four hours in a single bout |
A.It results in a higher death risk. |
B.It increases glucose and fat in the body. |
C.It makes a person unable to exercise long enough in a day. |
D.It causes the gene to fail to balance the glucose and fat in the body. |
A.improve | B.avoid |
C.ignore | D.achieve |
【小题1】C
【小题2】D
【小题3】D
【小题4】B
解析【小题1】 C
解析 标题归纳题。文章首先提出最新研究发现,即:久坐会致命。之后围绕该主题对研究进行介绍,并对此研究发现进行分析。故选C项。
【小题2】 D
解析 推理判断题。根据第五段第一句“‘After four hours of sitting,the body starts to send harmful signals’...”可推断选D项。
【小题3】 D
解析 细节理解题。根据第五段第二句“She explained that genes regulating(调节) the amount of glucose(葡萄糖) and fat in the body start to shut down.”可知,坐了四个小时后,身体会开始发出有害信号,此时调节体内葡萄糖和脂肪量的基因会停止工作,从而导致体内葡萄糖和脂肪量失衡。
【小题4】 B
解析 词义猜测题。最后一段中艾克布洛姆巴克的话是对“what might be possible to offset those effects”进行具体说明,即告诉人们如何避免久坐的不利影响,故选B项。
科目:高中英语 来源: 题型:阅读理解
Butterflies are some of the most fascinating and beautiful insects in the world. Adult butterflies will live about 2 to 4 weeks. They use their senses of sight, touch, hearing, smell, and taste to survive in the world, find food and mates, lay eggs in an appropriate place, migrate, and avoid hungry enemies.
Butterflies have large compound eyes, which allow them to see in all directions without turning their heads. Like most insects, butterflies are very nearsighted, so they are more attracted to a sea of flowers than individual plants. Butterflies do not “see” colors such as red, green, and yellow, but they can sense sunlight, which indicates the direction the sun is shining, as well as ultraviolet light, which is present on many flowers and guides butterflies to honey sources.
Butterflies have a very well-developed sense of smell, but it is not in their nose, since they don't have one. Sense receptors are located in their antennae, feet, and many other parts of the body. They can help butterflies find their favorite flower honey food, and mates.
Butterflies' feet have sense organs that can taste the sugar in flower honey, letting the butterflies know if something is good to eat or not. Some females also carefully choose host plants by tasting to find appropriate places to lay their eggs. Adult butterflies feed their babies using a long tube. Butterflies force blood into the tube to straighten it out, allowing them to feed. Butterflies get all their food from this tube.
Butterflies don't have ears. Instead they “hear” sounds through their wings by sensing changes in sound vibrations.
Butterflies may possess senses we don't even know about yet, because their body structure is very different from ours, and therefore difficult to understand, when observed through our own human senses.
【小题1】The text mainly focuses on ________.
A.butterflies' living habits | B.butterflies' beauty |
C.butterflies' senses | D.butterflies' daily activities |
A.Butterflies can see in all directions and don't need to turn heads. |
B.Butterflies have good eyesight. |
C.Butterflies are sensitive to bright colors including red and yellow. |
D.Butterflies cannot sense the ultraviolet light. |
A.To find highqualified honey. |
B.To have a good place for living. |
C.To make it easier for them to hide from the enemies. |
D.To find a proper place for their eggs. |
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科目:高中英语 来源: 题型:阅读理解
Pilling a cat can be a 'terrible” experience. Cats don’t want something pushed down their throats, and they’ll fight with all their strength to prevent it. In fact, it’s amazing how powerful their small bodies can be.
The easiest way of pilling a cat is to press the pill into powder. Then mix the powder with a small amount of wet food. If your cat usually eats dry food, she will probably view the wet food as a treat and eat it up.
If your cat won’t eat the wet food that contains the pill or if she is too ill to eat, you can get a “pill gun”. There are some basic instructions. Getting your cat’s mouth to open is going to be the most difficult part. First, be sure the pill is in a handy place. Then you can put your cat on a bookshelf with her bottom in a corner or you can put her on your lap firmly tied. Have your cat facing to the right if you’re right-handed. With your left hand, hold your cat at the cheekbones, putting your palm (手掌) at the top of her head. Keeping your finger off the trigger (扳机), with your right hand, Insert the pill gun until the pill is positioned over the tongue and open throat Be sure to give your cat a treat directly after giving the pill.
If you don’t feel comfortable using a pill gun, you can try giving the pill by hand. Push your cat’s head backwards just far enough so that her nose is pointing towards the ceiling. At this point, most cats will slightly open their mouths. With the little finger or ring finger of the hand holding the pill, open the bottom jaw a little more. You may need to hold her top jaw with your other hand while doing this. Aim straight and lightly throw the pill or drop it. Most cats will then swallow the pill.
【小题1】Pilling a cat can be a terrible experience because cats ______.
A.are amazingly powerful and dangerous |
B.may fight with all their strength against pills |
C.refuse something pressed down their throats |
D.are difficult to treat once they’ve got ill |
A.Wet food with medicine is usually a treat to cats. |
B.Cats used to dry food must reject wet food. |
C.The easiest pilling is to press the pill into powder. |
D.Cats arc most likely interested in something new. |
A.facing to the right | B.with your right hand |
C.at the head | D.on your lap firmly |
A.its nose is straight upwards | B.it is touched by fingers |
C.its head is turning around | D.it is served with its favorite pills |
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科目:高中英语 来源: 题型:阅读理解
Almost every machine with moving parts has wheels,yet no one knows exactly when the first wheel was invented or what it was used for.We do know,however,that they existed over 5,500 years ago in ancient Asia.
The oldest known transport wheel was discovered in 2002 in Slovenia.It is over 5,100 years old.Evidence suggests that wheels for transport didn’t become popular for a while,though.This could be because animals did a perfectly good job of carrying farming tools and humans around.
But it could also be because of a difficult situation.While wheels need to roll on smooth surfaces,roads with smooth surfaces weren’t going to be constructed until there was plenty of demand for them.Eventually,road surfaces did become smoother,but this difficult situation appeared again a few centuries later.There had been no important changes in wheel and vehicle design before the arrival of modern road design.
In the mid1700s,a Frenchman came up with a new design of road—a base layer(层) of large stones covered with a thin layer of smaller stones.A Scotsman improved on this design in the 1820s and a strong,lasting road surface became a reality.At around the same time,metal hubs (the central part of a wheel)came into being,followed by the pneumatic tyre(充气轮胎) in 1846.Alloy wheels were invented in 1967,sixty years after the appearance of tarmacked roads(柏油路).As wheel design took off,vehicles got faster and faster. (2013·重庆,C)
【小题1】What might explain why transport wheels didn’t become popular for some time?
A.Few knew how to use transport wheels. |
B.Humans carried farming tools just as well. |
C.Animals were a good means of transport. |
D.The existence of transport wheels was not known. |
A.It was easier than wheel design. |
B.It improved after big changes in vehicle design. |
C.It was promoted by fastmoving vehicles. |
D.It provided conditions for wheel design to develop. |
A.By giving examples. |
B.By making comparisons. |
C.By following time order. |
D.By making classifications. |
A.The beginning of road design. |
B.The development of transport wheels. |
C.The history of public transport. |
D.The invention of fastmoving vehicles. |
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科目:高中英语 来源: 题型:阅读理解
Plastic is one of the most important technological discoveries of the 20th century.However,it may soon be replaced.The new development—liquid wood—can replace plastics in all branches of modern industries.
Plastic as a material enjoys the biggest demand in the modern world,but it does have a number of drawbacks.First and foremost,plastic isn’t recyclable.Secondly,it contains toxins (毒物) helping develop cancerous diseases.Finally,it’s made of oil and oil reserves aren’t endless.
The liquid wood technology is likely to replace plastic and provide mankind with new materials for many years ahead.Norbert Eisenfreich,a senior researcher at the Faunhofer Institute for Chemical Technology (ICT) in Germany,said that arboform,the new material,is made of lignin (木质素),which can be obtained from soft tissues of wood.Once mixed with several other materials,it turns into solid and nontoxic alternative for plastics.
ICT team leader Emilia Regina InoneKauffmann said the woodworking industry separates wood into three basic components,including lignin.Lignin isn’t used for the production of paper.Specialists of ICT mixed lignin with several natural materials and thus invented the material which could be melted and molded (铸型).
When solid,arboform looks like plastic and possesses the qualities of polished wood.It can be used for the production of any items.Arboform is already used for the production of car parts which require extra strength.In addition,liquid wood can be recycled repeatedly.The material preserved all of its qualities even if it’s reprocessed ten times.
However,the new invention doesn’t enjoy an extensive use due to the high content of sulphur (硫) in it.German researchers are sure to reduce the amount of sulphur by 90 percent very soon to make arboform usable for home needs.
【小题1】According to the passage,plastic________.
A.plays a big role in the modern world |
B.helps to protect our environment in some way |
C.has been replaced by the newly discovered material |
D.helps us to reduce the use of petrol |
A.It is easily made from natural oil. |
B.It is more widely used in household. |
C.It is recyclable and friendly to the environment. |
D.It contains no poisonous materials. |
A.the material’s extensive use |
B.the content of sulphur in arboform |
C.the production cost of arboform |
D.the qualities of liquid wood |
A.advertise the new material—arboform |
B.introduce liquid wood which will replace plastic |
C.advertise new products made of arboform |
D.show readers how to produce arboform |
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科目:高中英语 来源: 题型:阅读理解
Rising levels of carbon dioxide in the atmosphere are a major cause of climate change, and now a new study has confirmed that atmospheric CO2 is also affecting the ocean chemistry and potentially harming sea life.
Montana State University scientist Robert Dore has been researching the water in the Pacific Ocean for almost two decades. "We've been going to the same spot in the Pacific Ocean, and we try and characterize long-term change in the open ocean environment. And one of the key things that we measure is COx levels. And We've been able to record this increasing quantity of atmospheric CO, into the ocean. "Scientists expected that as atmospheric CO2 increased, more and一 more of the carbon dioxide would be absorbed into the ocean, affecting the chemical balance of the sea water, with a potentially harmful impact on shellfish and coral in particular.
"As carbon dioxide dissolves in the water, or seawater in this case, it forms a weak acid, carbonic acid," Dore explains. "And therefore, as the concentration of CO2 in the atmosphere goes up and that exchanges with the surface seawater, it drives the pH down, and makes it more acidic."
The seawater samples Dow and his colleagues have analyzed confirm what the theory predicts. The effect was particular striking at about 250 meters down, and again at 500 meters. Dore and his colleagues came up with two possible explanations. It could be that surface water picked up CO2 and then moved to those depths. Or there could be a biological explanation.
"It's important to realize that the oceans are really becoming acidic. And it can have negative impacts on a whole variety of sea life from fish to coral. It’s potentially catastrophic."
【小题1】What can be the best title of the passage?
A.Sea Life Facing Danger | B.Scientist Researching Seawater |
C.Oceans Becoming More Acidic | D.Climate Change Affecting Seawater |
A.more corals will appear in the sea |
B.the surface water is becoming warmer |
C.the chemical balance of the seawater is affected |
D.the pH of the ocean out here has been increasing |
A.abcde | B.dbcea | C.aebed | D.edcba |
A.his research and analysis | B.the expectation of other scientists |
C.some former theory | D.a major cause of climate change |
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科目:高中英语 来源: 题型:阅读理解
While learning the science lessons,I used to get a doubt—why ear,nose,tongue and eyes should be called as special senses?The basic reason is that these are the channels through which we maintain contact with the surroundings.Though apparently it may feel like these are individual sensory organs,they do show some connectivity.Interestingly,our hearing is less sharp after we eat a heavy food.Isn’t it good for a sound nap after a stomachfull meal?That does not mean we go deaf after a meal,but the hearing pitch(强度) does change after a heavy meal.
We usually give credit of the taste to our tongue,but do you know that unless saliva(唾液) dissolves something,our tongue cannot recognize the taste of the food eaten.Taste is nothing but the food chemicals dissolved in the saliva being sensed by the taste buds present on the tongue.Try_to_dry_off_your_tongue_and_mouth_with_a_tissue_paper_and_then_taste_something.
Women are much better smellers than men.They are born with this characteristic ability and can correctly pinpoint the exact fragrance of the sample.We all can store almost 50,000 different scents(气味),which are strongly tied to the memories.
Pupils(瞳孔) do not respond to light alone,but to the slightest bit of noise around too.Thus surgeons,watchmakers and those professionals who have to perform a much delicate job do prefer to have a soundfree environment.Even a small noise can dilate(扩大) their pupils,change the focus and blur(使模糊) their vision.If you do not wear glasses or contact lens due to having a 6/6 vision,you are just among the one third of the human population.It is now statistically proved that only one third of the population has perfect vision,rest all are either wearing glasses or are trying to read with a compromised vision.
Each and every one of us has a particular or individualistic or characteristic smell,which is unique to us,except for the identical twins.This smell is very subtle(微妙的) yet can be sensed even by a newborn.It may be due to this scent that the newborn recognizes the presence of his parents around.Many of us can pinpoint the smell of our significant friends and colleagues.A significant part of this phenomenon is guided by genetics but it is also modified by the environment,diet and personal hygiene.This all together creates the unique chemistry that is individualistic for each person.
【小题1】We can learn from Paragraph 1 that ________.
A.after a full meal our hearing is as good as before |
B.all sensory organs are connected and can be exchanged |
C.sensory organs’ functions can never be changed for their particular character |
D.we feel and learn about the world around us through our eyes,ears,nose and tongue |
A.The functions of sensory organs. |
B.The connectivity of sensory organs. |
C.A newborn’s senses of the sensory organs. |
D.The differences of senses between women and men. |
A.Our tongues can’t be dried while eating something. |
B.If your tongue is dried without any saliva on it,it will not work. |
C.A tissue paper is the only thing that can be used to dry our tongues. |
D.If your tongue is dried with a tissue paper,it may work as well as before. |
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科目:高中英语 来源: 题型:阅读理解
Cloud seeding is a method of artificially causing clouds to produce precipitation (降水) in the form of rain or snow.Cloud seeding has also been used in attempts to modify the severity of hail storms and hurricanes.The effectiveness of cloud seeding remains controversial (有争议的).but it continues to be used in some regions to try to increase rainfall for agriculture and to build snow packs for water supplies and power production.
Cloud seeding was developed by American scientists Irving Langmuir and Vincent Joseph Schaefer during and after World War II.Their work began as an effort to learn more about the buildup of ice on airplane wings, and eventually led them to attempt to create rainfall by releasing several pounds of crushed frozen carbon dioxide into a cloud from an airplane.In this form, the carbon dioxide is called dry ice.On November 13, 1946, the technique appeared to produce snow directly under the cloud; the snow then turned to rain as it fell to the ground.
For their experiment, Langmuir and Schaefer selected a supercooled cloud, one in which the water droplets remain liquid in subfreezing temperatures.Their theory was that small grains of dry ice falling through the cloud would cause tiny droplets of water vapor in the cloud to freeze into crystals that attracted more water vapor.Their theory proved to be correct and eventually the crystals became heavy enough to fall from the cloud as snow.As the snow reached the warmer temperatures closer to the ground, it melted and became rain.
Another scientist, Bernard Vonnegut, produced a method of cloud seeding using silver iodide (碘化银).He used particles of silver iodide because its crystal structure resembled that of ice in clouds.Silver
iodide also had practical advantages over frozen carbon dioxide It could be stored at room temperature
and did not require an airplane as a delivery mechanism.Instead, silver iodide crystals could be fired by
cannons (大炮) high into the air, where wind carried them into the clouds.
【小题1】According to the text, Langmuir and Schaefer had intended to deal with__
A.how to freeze carbon dioxide
B.how to remove ice on plane wings
C.how to make weather forecast for the war
D how to hide planes in clouds at war
【小题2】What is the CORRECT order of the course for cloud seeding with dry ice?
a.snow becoming rain in wanner temperatures b.crystals attracting more water vapor
c.crystals falling in the form of snow d.crystals becoming very heavy
e.freezing tiny droplets of water vapor into crystals
f.putting small grains of dry ice in the cloud
A.a-c-f-d-b-e | B.b-f-e-a-c-d |
C.f-e-b-d-c-a | D.e-a-d-c-b-f |
A.it is much cheaper than dry ice | B.it can be stored at any rooms |
C.it can be sent into clouds by wind | D.it is similar |
A.Cloud Seeding |
B.Artificial Raining |
C.Weather Changing |
D.Cloud Gathering |
A.three | B.two | C.one | D.four |
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科目:高中英语 来源: 题型:阅读理解
When Hurricane Phailin hit India in late 2013, it became the largest storm to strike the subcontinent in over a decade. The storm affected more than 12 million people in India and neighboring countries, and damaged or destroyed many houses. However, good news is that cleverly-designed beach house created by architect Ray Huff can survive such strong winds and storm waves.
Located on the shore of an Indian island, Huff’s award-winning cube-shaped beach house was built to replace one smashed to pieces by Hurricane Phailin.
Huff pointed out that many houses built along shoreline were poorly constructed, and enforcement(执行) of building codes wasn’t strict. After Phailin’s attack, all new shoreline houses are required to meet stricter, better-enforced codes. The new beach house should be able to stand a Category 3 hurricane with peak winds of 179 to 209 kilometers per hour.
At first sight, Huff's house looks anything but hurricane-proof. Its redwood shell makes it resemble “a large party lantern” at night, according to one observer. But looks can be misleading. The house’s wooden frame is reinforced(加固) with long steel rods to give it extra strength.
To further protect the house from hurricane damage, Huff raised it 2.7 meters off the ground on pilings---long columns of wood anchored(固定) deep in the sand. Pilings might appear insecure, but they are strong enough to support the weight of the house. They also balance the house above storm waves. The pilings allow the waves to run under the house instead of running into it. “These swells of water come ashore at great speeds and cause most of the damage done to beach-front buildings,” said Huff.
Huff designed the wooden pilings to be partially hidden by the house’s ground-to-roof shell. “The shell masks the pilings so that the house doesn’t look like it’s standing with its pant legs pulled up,” said Huff. In case of a storm wave, the shell should break apart and let the waves rush under the house, the architect explained.
【小题1】After Hurricane Phailin, new houses built along shore line are required_____.
A.to be easily reinforced |
B.to look smarter in design |
C.to meet stricter building standards |
D.to be designed in the shape of cubes |
A.it is made of redwood |
B.it is in the shape of a shell |
C.it is strengthened by steel rods |
D.it is built with wood and stones |
A.support the weight of the house |
B.allow the waves to run through the house |
C.anchor stronger pilings deep in the sand |
D.prevent water from rushing into the house |
A.to give the house a better appearance |
B.to strengthen the pilings of the house |
C.to protect the wooden frame of the house |
D.to slow down the speed of the swelling water |
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